Center for wire ropes



2- E. w. BREWSTER 1,839,463

. CENTER FOR WIRE ROPES Filed Aug. 4, 1927 17711677107 Ezzw w. 237 601 by W dams/L KM patented Jan. 5, l d

UNETE STATES PATENT- orrrn ELLIS W. BREWSTER, E PLYMOUTH, SSAGEUSEITS, ASSIG-NOR T0 PLYMOU CORDAG-E COMPANY, OF NORTH PLYMOUTH, MASSACHUSETTS, A'COO'EION 0E massnon'csnrrs crav'rnn son wrnn no'rns Application filed August a, 1927. Serial Ito. 210,670.

This invention relates to improvements in centers for wire ropes. More particularly it relates to the central support or core upon which the several strands of wires are laid.

6 The best centers hitherto known have been ordinary ropes, carefully made of selected long vegetable fibres, as Java sisal, Mexican sisal or manila hemp.

It is important that in the manufacture of .1 wire rope the central filling shall have certain desired qualities in a very accurate degree, sincethe useful life of the wires of the rope depends in large measure upon whether or not the center performs its function in a satisfactory manner. In addition to having strength, durability and capability of being flexed without ill effect, the core material must be resistant to fresh and salt water, and to oil, coal-dust, grit, etc., to which the rope may be subjected. Avery important function of the center is that of supporting the strands of wire in their proper location relative to each other. In fact the filling material should have a peculiar combination of initial compressibility, or plasticity, and subsequent incompressibility, if it is to serve with a maximum of satisfaction. That is to say, an ideal would be attained if the material were compressibleinitially so as to afford a 3 cushion-like seat for the strands of wire, as laid upon it in rope formation, with the center being reshaped, under the constrictive pressure of the strands, so as more or less to fill the spaces between the strands; and if all further compressive stresses on the center were firmly and unyieldingly resisted, from the very instant at which the wire strands became properly seated, and so that they could not come actually into cont-act with .each other. If the center be too small or too soft to give this support nicking of the wires I will ensue, materiall shortening the useful life of the rope. o, the strands of wire will come into contact, and if further com- 7 pression takes lace, one of the strands will be forced out 0 position, causing uneven tension, and uneven wear.

At costs which compare favorably for weight and body of material with the cost of the manila hemp and sisal fibres hitherto used in fibre rope, paper materials are available; and methods for their manufacture are also relatively inexpensive. But as compared with hemp and sisal, when used in their normal long fibrous structure, a greater uniformity of size of centers can be attained with paper materials, producing a uniformity of support for the regularly laid wire strands and a combination of initial compressibilit with ultimate non-compressibility, which believe to be not found in the center of any rope now known in the industry.

11 a typical formation paper is composed of small cellular elements compacted together in sheet form under pressure. Such sheets can be slit into fairly narrow strips, almost of absolutely uniform width. And under uniformity of treatment by mechanism providing tension and twist and radial compression a greater uniformity of form and density results than where the initial unit is a fibre of hemp, as made by nature. This is true because individual fibres vary; and the mechanical processes for their collection and aggregation, and the drawing separation of the ag gregated masses into slivers are less accurate in the production of desired dimensions, tensions, and degrees of internal compression of the product. Also the paper elements can be assembled into many more forms of centers than can the usual long fibre stock, in each of which the paper material afiords a solid foundation. Strips of the paper stock, for example may be twisted to yarns, the yarns twisted to strands and the strands twist/ed to form a center according to conventional rope practice. But also, several of the yarns may be twisted together directly to provide a center; or, fiat strips of paper may be twisted to form a center without preliminary twisting of the individual strips into yarns. Again the flat strips may be wound helically in smoothlayers over a core of paper or other material made in any suitable manner, a construction which makes possible an exceedingly solid filler, the degree of solidity of which can be controlled more or less by the character of the core. Each of the possible formations can conveniently be-made with uniformity of size and of compactness to pro- 100 strips to yarns;

vide cushion seats for the wire strands as these are laid in wire rope formation. The proper compactness can be ascertained, by experiment for each particular paper stock and formation, so that the center will yield enough under the pressure of the strand to bulge into the interstices between adjacent wire strands, thus making a longer initial bed of contact between center and strand than is feasible with a tightly laid hemp rope center; and so that any subsequent compressive stresses exerted by the wire strands on the paper center, as when the rope is bent around a wheel, will be unyieldingly resisted by the center, because it has then been compressed to a point where it will lend thus firm support to the strands, and because there is less space remaining available between strands into which it can move in response to increased pressure. To provide a lubricant for the center, and also for the wires, as is now the practice, the paper material is readily absorbent of the lubricant, which ma be grease, oil or other suitable substance. y treating the paper centers in any approved manner the lubricant not only inures for the benefit of the filler but also is supplied to the wires, at places where these are in close association with the paper. Also the treated paper becomes resistant to water, and is not affected in any discernible degree by extraneous substances which may penetrate to the center of the rope.

Another feature of practical utility is the ability of the paper center to receive and hold legible imprint. This may be important for identification purposes. Obviously it is a distinct advantage to have a material, of which the center is made, which is capable of being printed. The matter printed thereon will be concealed and protected during the use of the rope, but will be made available by unlaying the rope whenever access is desired to the information thus printed.

Thus the invention provides a product which is of considerable importance in the art of wire rope manufacture. It will be. understood that the embodiments herein set forth are merely examples of various possible embodiments thereof.

It is intended that the patent shall cover by suitable expression in the appended claims whatever features of patentable novelty exist in the invention disclosed.

In the accompanying drawings:

Figure 1 shows a center for wire rope, made of strips of aper twisted to yarns, yarns in turn twisted to strands, and the strands in turn twisted to form the center.

Figure 2 shows several yarns, similar to those of Figure 1, twisted together directly into a center;

Figure 3 shows several of the flat strips of paper twisted into the form of a center, without preliminary twisting of the individual Figure 4 illustrates how a center may be built up by winding the strips of paper, in fiat form, in layers on a core which also is formed of paper; and

Figure 5 is a cross-section of a wire rope embodying a paper center made according to the invention.

Referring to Figure l'of the drawings, strips 10 of paper, are twisted into yarns 12, each single strip making a yarn. Then a multiplicity of yarns 12 are twisted together into strands 14; and three strands 14 are twisted to form the completed center 16.

In Figure 2 a multiplicity of yarns 12 are twisted together directly into the form of a center 18.

In Figure 3 the fiat strips 10, without being individually twisted to yarns, are twisted together to form a center 20.

In all three of these forms, the degree of twist given to the material will control the compactness of the completed product, but each permits attainment of the desired characteristics which heretofore have been described.

The form of center seen in Figure 4 eliminates the need for twist of the paper strips 10. Here they are wound helically in layers,

in flat formation, over a 'core 22. This cpre, preferably, is made of paper, twisted or otherwise formed into a uniform and suitably firm foundation. The strips may be wound in reverse direction in the several layers as illustrated, or may be wound all in the same direction. A center made thus in layers can be exceedingly solid, but, by employing a core 22 having a desired degree of compressibility the center as a whole may be made to give the needed initial cushioning efi'ect which has been described. The wound material, upon being compressed by the wire from all directions, becomes a bit concave exteriorly and fits around the adjacent wire strand surfaces.

Figure 5 is a cross-section of a wire rope embodying six strands 24 and center 26 which may be considered to be any one of those seen in Figures 1 to 3. The paper filler has yielded slightlyunder the pressure of the strands, and it fills, more or less completely, the small spaces between them. This slight initial yielding of the filler however, is all that it will undergo, in a properly designed rope, because it has been compressed its limit in reaching this stage, so that it henceforth will unyieldingly resist any subsequent compressive stresses. It has .been rendered so compact that it will provide a permanent firm support for the strands of wire under all conditions. When treated with any of the usual waterproofing and lubricatingsubstances my paper centers will be preserved and continue to serve indefinitely the functions which are so important to esaaee be maintained during continued use of the gin'ce paper may be had in abundance, the cost of material for my improved centers is at least as low, and perhaps considerably lower than the cost of the long-fibred stock now commonly used. The process of making the centers is much more simple and inexpensive. These practical advantages, coupled with the several structural advantages make the invention one of considerable importance in the art.

However, the durability will depend in part on the choice of stock from which to manufacture the paper. If the stock be what is known as rope stock, made from old manila ropes, the pulp and the paper made from it will have the same ultimate cellular structure as a manila rope center would have. The manila fibres each of several feet length, which make up ordinary rope, will have been disintegrated into their ultimate component fibres of microscopic length; and these latter will have been reformed into a thin, highly flexible mass (sheet or sheets of paper) which -in turn will have been formed into a stout composite mass (the center), having a slight plasticity, in which the ultimate cellular strength for resisting compression is the same as the material of the rope would have been. For some Wire ropes however, other cellular structure can be used, and kraft paper appears strongly resistant to compression when made up in accordance with the invention. V

Uther paper or fibre board stocks may be used, and treated papers, as the uniformity of working and of dimensional results is irrespective of the particular variety of material. As all such are in the general nature of paper, both as to their material, their structural characteristics and the machinery for their manufacture, they are to be understood as included within the generic term paper used herein.

ll claim as my invention:

, l. The combination, with the wire strands carrying tensile stresses in a Wire rope, of a center made of paper of vegetable origin carrying the compressive stresses imposed by the strands; said paper being a compact body deformed slightly from rotundity to conformity with the adjacent surfaces of wire strands, and constituting an approximately incompressible mass, filling the central space and projecting thence into the interstices between the said strands.

2. The combination, with the wire strands carrying tensile stresses in a wire rope, of a center made of paper sheets of vegetable origin carrying the compressive stresses imposed by the strands; said sheets constituting a compact body deformed slightly from rotundity to conformity with the adjacent surfaces of wire strands, and constituting an individual wires thereof which are toward the 1 center pressing against the center on curved surfaces of contact therewith covering substantial areas of the said wires individually and of the strands of which said wires are a part.

3. The combination, with thewire strands carrying tensile stresses in a wire rope, of a center made of strips of paper of vegetable origin carrying the compressive stresses imposed by the wires; said strips of paper being twisted and being in a compact body deformed slightly from rotundity to conformity with the adjacent surfaces of wire strands, and constituting an approximately incompressible mass having substantially the shape of the axial space defined by the wire surface which face toward the axis and being held in said shape by stress of said wires.

4. The combination, with the wire strands carrying tensile stresses in a wire rope, of a center made of strips of paper of vegetable origin carrying the compressive stresses imposed by the strands; said strips of paper being twisted and being in a compact body deformed slightly from rotundity to conformity with the adjacent surfaces of wire strands, and constituting an approximately incompressible mass, flexible with the wire, in which the strands are embedded.

5. An intermediate product in manufacture of wire ropes, comprising an attenuated, cylindrical, compact body of paper of vege? table origin; being of such slight plasticity as to yield and become deformed under the initial compressive stress of the strands when these are wound upon it, and having such compactness and rigidity that it is adapted by said slight yielding, to become non-compressible by subsequent stresses imposed by the strands.

6. The combination, with the wires carrying tensile stresses in a wire rope, of a center carrying compressive stresses imposed by the wires and comprising a pulped material of vegetable origin, the elemental fibres of which pulped material have been reassembled and compressed together.

7, The combination, with the wires carrying tensile stresses in a wire rope, of a center carrying compressive stresses imposed by the wires and comprising a pulped material of vegetable origin, the elemental fibres of which pulped material have been matted together and formed into a dense body capable of resisting compressive stress.

8. The combination, with the wires carrying tensile stresses in a wire rope, of a paper center carrying compressive stresses imposed by the wires and consisting of a mass of elemental fibres disorganized from vegetable stock and reorganized into the form of paper.

9. The method of making a wire rope, comprising the disintegrating of vegetable stock into the elemental fibres; the reorganizing of the said elemental fibres by the deposition thereof in the form of paper; the twisting of the paper; and the applying of the wires of the Wire rope compressively about said twisted paper.

10. The combination, with the wires car- .ryin'g tensile stresses in a wire rope, of a center carrying compressive stresses imposed by the wires and comprising paper of vegetable origin.

11. The combination, with the wires carry- 7 ing tensile stresses in a wire rope, of a composite center carrying compressive stresses imposed by the wires and comprising a body of twisted paper of vegetable origin.

12. The combination, with the wires carrying tensile stresses in a wire rope, of a center carrying compressive stresses imposed by the wires and consisting of a mass of elemental fibres disorganized from long vegetable fibre rope stock and reorganized into the form of paper and further formed as a rope.

13. The method of making a-wire rope, comprising the disintegrating of rope stock of the long fibred vegetable variety into the elemental fibres of its said long fibres; the reorganizing of the said elemental fibres by the deposition thereof in paper; the twisting of the paper; and the applying of the wires of the wire rope compressively about said elemental fibres as they are organized in said twisted paper.

14. In combination with the wire strands carrying the tensile stresses-in a wire rope, a composite paper center initially provided with a smooth, cylindrical exterior surface and subsequently deformed from rotundity into conformity with the adjacent wire strands, said center serving as a substantially continuous support for each such wire strand.

15; In combination with the wires carrying the tensile stresses in a Wire rope, a center comprising a firm mass of a compacted, pulped material of vegetable origin, the surface of which mass has continuous helical grooves conforming to the interior faces of,- and filling the interstices between, the wires which contact therewith.

Signed at Plymouth, Massachusetts, this 27th day of July, 1927.

ELLIS W. BREWSTER.

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